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Background: A retrospective evaluation of tolerance and efficacy of two schemes of neoadjuvant treatment in patients (pts) with unresectable rectal cancer: radiochemotherapy (CRT) and radiotherapy (RT), including conventional and accelerated hyperfractionation. Material and Method: A total of 145 consecutive pts with unresectable, locally advanced rectal cancer. The schemes used are RT in 73 (50%) or CRT in 72 (50%). In CRT, 54 Gy in 1.8 Gy fractions was given with chemotherapy, In the RT group, conventional fractionation (CFRT) and hyperfractionated accelerated radiotherapy (HART). HART was introduced at first as an alternative to CFRT, after radiobiological studies suggesting a therapeutic gain of hyperfractionation in other cancers, and second to administer relatively high dose needed in unresectable cancer, which is not feasible in hypofractionation because of critical organs sensitivity to high fraction doses (fd). HART was an alternative option in pts with medical contraindications to chemotherapy and to shorten overall treatment time with greater radiobiological effectiveness than CFRT. Results: Objective response (OR) in the RT and CRT group was 60% versus 75%. Resection rate (RR) in RT and CRT: 37% versus 65%. Tumor mobility and laparotomy-based unresectability were significant factors for OR. Performance status (PS), tumor mobility, and neoadjuvant treatment method were significant for RR. [ABSTRACT FROM AUTHOR]

Rotationally resolved fluorescence excitation spectra of three vibronic bands in the S1←S0 transitions of 1- and 2-methylnaphthalene (1 and 2MN) have been obtained. Each band exhibits perturbations that are produced by an interaction between the restricted torsional motion of the attached methyl group and the overall rotational motion of the entire molecule. A complete analysis of these effects yields values of the torsional barrier heights, the rotational constants, and the torsion–rotation perturbation coefficients of all vibronic levels that participate in the transitions. These values depend significantly on the position of the methyl group attachment, on the electronic state of the naphthalene chromophore, and on its vibrational state, as well. For example, V3 (the threefold torsional barrier) decreases from 809 cm-1 in 00 1MN to 128 cm-1 in 00 2MN. D (the largest first-order torsion–rotation perturbation term) increases from 0.03 MHz in 00 1MN to 406 MHz in 00 2MN, a change of more than 4 orders of magnitude. The V3 values of 00 and 81 1MN are 563 and ≤ 373 cm-1, respectively. A full discussion of these dynamically relevant effects and their dependence upon both electronic and geometric factors is given. [ABSTRACT FROM AUTHOR]

We have observed, and assigned, the fluorescence excitation spectrum of the 000 band in the 1B1←1A1 electronic transition of pyrimidine, at a resolution of ∼10 MHz. The rotational constants of the 1B1 state, the lowest excited singlet state, are A’=6352±3, B’=5853±3, and C’=3042.0±0.5 MHz. The magnitudes of these constants are not very different from those of the ground (1A1) state. However, the in-plane a and b inertial axes in the 1B1 state are rotated by 90° with respect to those of the 1A1 state. The spectrum also exhibits numerous perturbations, evidenced by the presence of extra lines, anomalous intensities and lifetimes, and shifts of the main lines from their expected positions. The perturbations are strongly magnetic-field dependent, demonstrating that they arise from an intramolecular coupling of the 1B1 state with nearly isoenergetic rovibronic levels of a lower triplet (3B1) state. Models are proposed to account for this behavior based on a deconvolution of the experimental spectrum and simulations of the observed Zeeman effects. The most satisfactory interpretation of the data (in the language of the zero-order states) is obtained if it is assumed that a single rovibronic 1B1 level is spin–orbit coupled to one or a few 3B1 levels, which in turn are coupled via rotationally dependent Coriolis interactions to a dense manifold of background levels, probably those of the 1A1 state. Because the latter coupling is small, typically less than the linewidths in the spectra, it is manifested only in a K’+1 dependence of the lifetimes of selected molecular eigenstates and the reduced g values required to fit the magnetic-field dependence of their spectra. [ABSTRACT FROM AUTHOR]

In this paper we fit low-resolution spectra of pyrazine by assuming Coriolis coupling between S1 and {S0}. Evidence for Coriolis coupling is particularly obvious in the rovibronic spectra of pyrazine-d3h1 of which we give high resolution examples. For the lowest rotational temperature we noticed a non-Boltzmann distribution of the J‘=0 ground state, which is probably caused by a bottleneck for ΔJ‘=-2 transitions. Using the lifetimes of molecular eigenstates belonging to P(1) we can calculate the absolute quantum yield of the vibrationless and rotationless 1B3u state. Using this number and the obtained interstate Coriolis coupling rate constants we calculate the variation of the absolute quantum yield across the rotational contour. For low J we get satisfactory agreement with experiments, but for high J our calculations drop off too fast with J. We explain this by the fact that at high J values triplet decay becomes dominant because of K scrambling in the triplet manifold. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyse the prognostic factors in postoperative prostate cancer irradiation and develop a nomogram for disease-free survival (DFS).

Abstract: Aims: To evaluate the incidence, severity and kinetics of acute and late toxicity from bladder and bowels in patients with bladder cancer treated with radical radiotherapy. Materials and methods: The retrospective analysis was based on 487 patients with T2, T3 bladder cancer, treated with radiotherapy between 1975 and 1995. The pelvis was irradiated electively in 303 patients; in the remaining patients, the bladder alone was treated. The mean total radiation dose to the bladder was 65.5Gy. Various schedules of protracted, conventional and accelerated radiotherapy were used. The influence of selected factors on maximum acute toxicity and late toxicity was assessed. The kinetics of acute toxicity was also evaluated. The median follow-up was 76 months. Results: Seven patients did not complete treatment due to excessive acute toxicity. The incidence of grade ≥3 acute bladder and bowel toxicity was 5 and 3%, respectively. The actuarial, 5-year incidence of grade ≥3 late bladder and bowel toxicity was 12 and 3%, respectively. The most important factors influencing acute toxicity were: T-stage (P =0.004) for the bladder and pelvic irradiation (P =0.044) and dose intensity (P =0.000) for the bowels. The latency of both early bladder and bowel toxicity was correlated with dose intensity. The most important factor influencing late bladder toxicity was acute toxicity score (P =0.000). Late bowel toxicity was also influenced by acute bowel toxicity (P =0.04). Conclusions: The severity of acute bowel toxicity is related to pelvic irradiation and dose intensity. The severity of acute bladder toxicity depends on T-stage. The increase in dose intensity is associated with shorter latency to maximum acute bladder and bowel toxicity. The severity of acute bladder and bowel toxicity influences the risk of late effects from those organs. [Copyright &y& Elsevier]